According to our models of the universe, filaments of dark matter connect massive objects like galaxies and galaxy clusters in a vast cosmic web. Hydrogen flows through here, feeding on galaxies, but it is not at all easy to see due to the weak emission of diffuse hydrogen in intergalactic space.
But we have gone one step further. An international team of astronomers led by Roland Bacon of the Lyon Astrophysical Research Center in France has just obtained direct images of various filaments of the cosmic lattice in the early universe, approximately 12 billion light-years away.
This discovery could drastically alter our understanding of galaxy formation in the infancy of the universe.
Bacon and his team observed a small part of the sky for a long, long time, with the MUSE instrument on ESO's Very Large Telescope in Chile. After 140 hours of observations of a section of the sky that also appeared in the ultra-deep field of the Hubble Space Telescope and processing and analyzing the data, which took another year, they discovered that they had captured images of bright hydrogen in filaments of the cosmic web, spanning millions of light years.
Reference: Roland Bacon et al. The MUSE Extremely Deep Field: the Cosmic Web in Emission at High Redshift. Astronomy and Astrophysics (2021). Doi: https://doi.org/10.1051/0004-6361/202039887
